Gasket assembly having isolated compression limiting device

ABSTRACT

A manifold gasket includes a carrier frame with a plurality of media-conveying openings corresponding to openings communicating between two parts to be clamped, such as an intake manifold and a cylinder head. Elastomeric sealing material is molded to the carrier frame about the openings to seal the openings when clamped. A compression limiting device is disposed on the carrier frame and is isolated from direct contact with the carrier frame by intervening elastomeric bonding material to limit compression of said elastomeric sealing material when the gasket is clamped between the head and block. The elastomeric bonding material renders the compression limiting device free-floating relative to the carrier frame.

This application is a continuation of U.S. Ser. No. 11/193,810, filedJul. 29, 2005, now U.S. Pat. No. 7,306,235.

BACKGROUND OF THE INVENTION

1. Technical Field

This invention relates generally to static gasket assemblies of the typeused to form a seal at a joint where two members are clamped togetherand more particularly to such gaskets having features to limit thecompression of the elastic seal elements.

2. Related Art

It is common in many applications to provide a static gasket to seal thejoint between two members that are clamped together in order to providea fluid-tight seal to media conveyed through openings between themembers and through the gasket. It is common for such gaskets to havesome type of rigid carrier frame onto which beads of rubber or otherelastomeric materials are molded to provide an effective seal undercompression.

In one known gasket assembly, the carrier frame is fabricated of plasticand has a thickness, particularly in the regions of the sealing beads,that is effective to limit the amount by which the elastomeric sealingbeads can be compressed. At maximum compression, the mating surfaces ofthe clamped members confront corresponding stop surfaces on the plasticcarrier frame thereby precluding further compression of the elasticsealing beads. While this arrangement is effective at controlling thecompression of the elastic sealing beads, it requires that the plasticcarrier body be sufficiently thick and strong so as to withstand theclamping loads without breaking.

SUMMARY OF THE INVENTION AND ADVANTAGES

A gasket assembly for an internal combustion engine includes a carrierframe having a plurality of media-conveying openings. Elastomericsealing material is molded on the carrier frame in surrounding relationto at least some of the openings and project outwardly of the carrierframe so as to be elastically deformable when the gasket assembly iscompressed to provide a seal about the intake openings. A compressionlimiting device is disposed on the carrier frame and isolated fromdirect contact with said carrier frame by intervening elastomericbonding material to limit compression of said elastomeric sealingmaterial when said gasket is clamped between the head and block.

The elastomeric bonding material is advantageous in that it renders thecompression limiting device free-floating relative to the carrier frame.Such a free-floating limiter promotes even distribution of the sealingelements while still limiting the amount by which the sealing elementscan be compressed.

Use of the isolated compression limiting device has the furtheradvantage of relieving the carrier frame itself from also serving as acompression limiter. This, in turn, increases the available sealing areafor the sealing material, thereby enhancing the sealing effectiveness ofthe gasket.

The compression limiting device may further include a locator pinprojecting from a compression limiting surface of the compressionlimiting device. The locator pin has the advantage of helping locate thegasket in proper alignment during installation and use of the gasket.

THE DRAWINGS

These and other features and advantages of the present invention willbecome more readily appreciated when considered in connection with thefollowing detailed description and appended drawings, wherein:

FIG. 1 is a perspective view of a gasket assembly constructed accordingto a presently preferred embodiment of the invention;

FIG. 2 is an enlarged fragmentary perspective view of a portion of FIG.1;

FIG. 3 is an enlarged cross-sectional view taken along lines 3-3 of FIG.2; and

FIG. 4 is a view like FIG. 3, but showing the gasket installed in useunder compression.

DETAILED DESCRIPTION

A gasket assembly constructed according to an embodiment of theinvention is shown generally at 10 in FIG. 1 and includes a carrier bodyor frame 12 providing a rigid framework of the gasket assembly 10. Theframe 12 may be fabricated from any suitable material, such asaluminized steel or the like. The assembly 10 is formed with a pluralityof media-conveying openings. The illustrated example shows an intakemanifold gasket 10 having a plurality of air intake openings 14 andengine coolant openings 16. The gasket 10 is used for scaling the jointbetween an intake manifold 18 and a cylinder head 20 (FIG. 4). Theopenings 14, 16 correspond with associated openings in the intakemanifold 18 and cylinder block 20 to enable flowable media, such as airand engine coolant, to be conveyed between the intake manifold 18 andcylinder head 20 through the openings 14, 16 respectively in the gasketassembly 10.

Beads of elastomeric sealing material 22 (such as rubber or the like)are molded to the carrier body 12 about each of the respectivemedia-conveying openings 14, 16 in order to provide a fluid-tight sealabout the openings when the manifold 18 is bolted to the cylinder head20. The sealing beads 22 project from the carrier body 12 on oppositesides thereof, such that the sealing beads 22 are elastically compressedwhen clamped between the intake manifold 18 and cylinder head 20(compare FIGS. 3 and 4).

A load or compression limiting device 24 is disposed on the carrier body12 adjacent at least one of the openings 14, 16. The device 24 hasopposite compression limiting surfaces 26, 28 which define a thicknesst₁ of the limiting device 24 that is greater than the thickness t₂ ofthe carrier body 12 in the area immediately surrounding the openings 14,16, but being lesser in thickness than the maximum thickness t₃ of thesealing beads 22 when in an uncompressed condition (FIGS. 2 and 3). By“effective thickness”, it is meant to account for any interveningcarrier material than may be present when measuring the sealing beadsthrough the thickness of the gasket assembly 10 from peak to peak. Thecompression limiting device includes an outer peripheral side surface 29which is spaced from direct contact with the carrier frame 12. Thecompression limiting device 24 is formed as a separate piece from thecarrier frame 12 and is mounted on the carrier frame 12 by a band ofintervening elastomeric bonding material 31. This material 31 surroundsthe device 24 about its peripheral side surface 29 and in doing soisolates the device 24 from direct contact with the carrier frame 12.This allows the device 24 to float relative to the carrier to the extentallowed for by the material 31. As such, misalignment that may occurbetween the clamping surfaces can be accommodated by the device bytilting or moving as necessary relative to the carrier frame 12 toachieve the compression limiting function in order to maximize thesealing effectiveness of the beads 22. The device 24 may be fabricatedof a suitable metal, such as stainless steel or the like, but theinvention is not limited by the selection of materials.

The compression limiting device 24 further includes a locator pinportion 30 that projects outwardly from one of the compression limitingsurfaces 26, 28 for receipt in a locating hole 32 of one of the clampingsurfaces of either the intake manifold 18 or cylinder block 20. FIG. 4illustrates the gasket assembly 10 in the fully clamped position, whereit can be seen that the locator pin 30 is received in a locating opening32 of the cylinder head 20 and where the intake manifold 18 and cylinderhead 20 are clamped together sufficiently to compress the sealing beads22 to the point where the clamping faces 33, 35 of the intake manifoldand cylinder head 18, 20 confront the compression limiting surfaces 26,28 of the compression limiting device, thereby precluding furthercompression of the sealing beads 22. The compression limiting device 24may include a hole 21 adjacent the locator pin 30 for accommodating abolt (not shown) used for clamping the manifold 18 to the head 20.

The compression limiting device may be located adjacent a central one ofthe media conveying openings 14 approximately midway between thelongitudinal ends of the carrier body 12. As illustrated in FIG. 1,there may be three such air intake openings 14 in linear succession anda single limiting device 24 associated with the middle one of the threeopenings 14. It will be seen that additional compression limitingdevices 34 may be provided at the opposite ends of the carrier body 12,but they do not include the locator pin feature as does the device 24.

By locating the compression limiting device 24 at the critical areawhere the head 20 and manifold 18 come together at a machined pad (i.e.,the center of the gasket) the device 24 effectively precludesovercompression of the gasket in the central regions and frees up spaceon the carrier body 12 around the openings 14, 16 in order to increasethe available sealing area for the sealing beads 22, thereby increasingthe sealing effectiveness of the gasket assembly 10.

Obviously, many modifications and variations of the present inventionare possible in light of the above teachings. It is, therefore, to beunderstood that within the scope of the appended claims, the inventionmay be practiced otherwise than as specifically described.

What is claimed is:
 1. A gasket assembly for an internal combustionengine comprising: a carrier frame having a plurality of intakeopenings, said carrier frame being generally planar with an uppergenerally planar surface and a lower generally planar surface;elastomeric sealing material bonded on said carrier frame in surroundingrelation to each of said openings, said elastomeric sealing materialpositioned on both of said upper and lower generally planar surfaces andhaving portions thereof projecting outwardly transverse to said upperand lower generally planar surfaces; said elastomeric sealing materialbeing elastically deformable when the gasket assembly is compressed toprovide seals about said openings; and a compression limiting devicehaving opposed compression limiting surfaces and being embedded in saidelastomeric sealing material adjacent to one of said openings; saidcompression limiting device being a solid metal block-like structure andhaving an upper surface, a lower surface, and side surfaces; saidelastomeric material embedding said compression limiting device at leaston all of said side surfaces; said gasket assembly having a firstthickness at said outwardly projecting portions of said sealingmaterial, a second thickness at said generally planar carrier frame, anda third thickness between opposing surfaces of said compression limitingdevice; said third thickness being greater than said second thickness,and said first thickness being greater than both said second and thirdthicknesses; wherein over-compression of said elastomeric sealingmaterial is precluded.
 2. The gasket assembly as set forth in claim 1wherein said opening in which said compression limiting device isadjacent to has a polygonal shape with a plurality of edges, each with adefined length, and wherein said compression limiting device extends inlength less than the length of said edge in which it is adjacent to. 3.The gasket assembly as set forth in claim 1 wherein said compressionlimiting device is made of a metal material.
 4. The gasket assembly asset forth in claim 3 wherein said compression limiting device is made ofa solid metal material.
 5. The gasket assembly as set forth in claim 1wherein said compression limiting device is connected to said carrierframe only by said elastomeric sealing material.
 6. The gasket assemblyas set forth in claim 1 wherein said carrier frame is made of a metalmaterial.
 7. The gasket assembly as set forth in claim 1 wherein saidcarrier frame is made of a plastic material.
 8. The gasket assembly asset forth in claim 1 wherein said elastomeric sealing material comprisesrubber.
 9. The gasket assembly as set forth in claim 1 wherein saidcompression limiting device is free floating relative to said carrierframe as permitted by said elastomeric sealing material in which it isembedded.
 10. The gasket assembly as set forth in claim 1 wherein saidelastomeric sealing material comprises sealing beads.
 11. The gasketassembly as set forth in claim 1 wherein said elastomeric sealingmaterial also projects radially into said openings.
 12. The gasketassembly as set forth in claim 1 wherein said compression limitingdevice is circumferentially discontinuous relative to said opening whereit is positioned adjacent thereto.
 13. The gasket assembly as set forthin claim 1 wherein there are three intake openings in said carrier frameand elastomer sealing material is bonded circumferentially around eachof said intake openings.
 14. The gasket assembly as set forth in claim13 wherein said three openings are substantially in line and saidcompression limiting device is embedded in elastomeric sealing materialadjacent a middle opening of said three intake openings.
 15. The gasketassembly as set forth in claim 1 further comprising a pin memberpositioned on said compression limiting device.
 16. The gasket assemblyas set forth in claim 15 wherein said pin member projects outwardlytransverse to one of said opposed compression limiting surfaces on saidcompression limiting device.
 17. The gasket assembly as set forth inclaim 1 further comprising an opening in said compression limitingdevice.
 18. The gasket assembly as set forth in claim 1 wherein saidcompression limiting device further comprises a solid polygonal volumewith substantially straight side surfaces.
 19. The gasket assembly asset forth in claim 1 wherein the compression limiting device has alength which is less than a segment of the opening.
 20. A gasketassembly for an internal combustion engine comprising: a carrier framehaving a plurality of intake openings, said carrier frame beinggenerally planar with an upper generally planar surface and a lowergenerally planar surface; elastomeric sealing material bonded on saidcarrier frame in surrounding relation to each of said openings, saidelastomeric sealing material positioned on both of said upper and lowergenerally planar surfaces and having portions thereof projectingoutwardly transverse to said upper and lower generally planar surfaces;said elastomeric sealing material being elastically deformable when thegasket assembly is compressed to provide seals about said openings; anda compression limiting device having opposed compression limitingsurfaces and being embedded in said elastomeric sealing materialadjacent to one of said openings; said compression limiting device beinga solid metal block-like structure and having an upper surface, a lowersurface, and side surfaces; said elastomeric material embedding saidcompression limiting device at least on all of said side surfaces; saidcompression limiting device is connected to said carrier frame only bysaid elastomeric sealing material; said gasket assembly having a firstthickness at said outwardly projecting portions of said sealingmaterial, a second thickness at said generally planar carrier frame, anda third thickness between opposing surfaces of said compression limitingdevice; said third thickness being greater than said second thickness,and said first thickness being greater than both said second and thirdthicknesses; and wherein over-compression of said elastomeric sealingmaterial is precluded.
 21. The gasket assembly as set forth in claim 20wherein said compression limiting device is made of a metal material.22. The gasket assembly as set forth in claim 20 wherein saidcompression limiting device is made of a solid metal material.
 23. Thegasket assembly as set forth in claim 20 wherein said carrier frame ismade of a metal material.
 24. The gasket assembly as set forth in claim20 wherein said carrier frame is made of a plastic material.
 25. Thegasket assembly as set forth in claim 20 wherein said elastomericsealing material comprises rubber.
 26. The gasket assembly as set forthin claim 20 wherein said elastomeric sealing material comprises sealingbeads.
 27. The gasket assembly as set forth in claim 20 wherein thereare three intake openings in said carrier frame and elastomer sealingmaterial is bonded circumferentially around each of said intakeopenings.
 28. The gasket assembly as set forth in claim 20 wherein saidthree openings are substantially in line and said compression limitingdevice is embedded in elastomeric sealing material adjacent a middleopening of said three intake openings.
 29. The gasket assembly as setforth in claim 20 further comprising a pin member positioned on saidcompression limiting device.
 30. The gasket assembly as set forth inclaim 20 wherein said pin member projects outwardly transverse to one ofsaid opposed compression limiting surfaces on said compression limitingdevice.